Improvement in hoisting-tackle



UNIT D STATES ATENT FFtcE.

" J. w. noncnoss, or MIDDLETOWN, oounncrtcc'r.

IMPROVEMENT IN HOlSTlNG-TA'CKLE. v

Specification forming part of Letters Patent No. 5 L742, dated December 26,1865.

.To all when), it may concern:

. Be it known that L'Josnrn W. Noncnoss,

' of Middletown, in thecouutyof Middlesex and .Figure 1 represents a sectional side elevation of this intention Fig. 2 is a sectional.

front elevation of the same; Fig.3 is a detached side elevatiouof the clevis, which is cast int-othedouble block. Fig. 4 is a horizontal section of the same, the line a: :0, Fi 3,, indicating the plane of section. Fig. 5 1s a the clevis has to-be secured to the center pin, I

horizontal section of the single block, taken in the planeiud icated by the line g y, Fig 2. indicate like provided with rihs-g'omt'heir ontersrrrtaees;

Similar letters of reference patts.

Thisiuveution consists, first, in the con-- struction ofa cast-metal block with a suitable wroughbiron or steel hook and clevis connection in such a mannerthata cheap and durable block is obtained, the hook or clevisof which is 'not liable to give way before any of the other parts; also, in forming in the lower end .of the's'iu'gle block a concave seat; for the becket in such amanner that the hoisting-rope can be secured quite close to the sheave, and the largest possible amount of hoistiug-rooui is obtained; finally, in the arrangement of ribsagainst the ends of which the bosses on the" ends of the clevis rests, and thus relieve the center pin partially or wholly of the strain to which the pin is exposed. I

Heretojore castor malleable iron has been employed in the manufacture of small blocks only because the hooks and eyes or other parts thicker than a quarter of an inch cannot very well be annealed, and the blocks could not be increased beyond a certain size, not because the diflerent parts of the shell of the block could not be made strong enough, (that-might have been accomplished without increasing the thickness of the block beyond proper limits,) but because the hook and clevis, on account of their-greater thickness, could not be annealed, and they would consequently be too weak to resist the required pressure. This difiiculty is obviated by my present invention, which relates to a block,-A, to which the clevis B is secured by casting the same as shown in i Figs. 1,3, and 4, said clevis extending down flush with'thc central partiti'omd, of thedou-' ble block, and madeto straddle or. tocatch over thecenter pin,'d, and, if desired, said clevis may be provided with recesses 0; into which the liquid metal runs during the process of casting; and by these-means is firmlyretaiued; or, instead of the recesses, the clevis may be provided with a head'or heads, which will produce'the same effect. In order to preventthe clevis from workingjloose sidewi'se, it is provided with V-shaped edges, as shown inEig. 4. 'The book G. and the clevis B can, thus be nadeofiwrought-iron or steel and-of any desired streugth,:wh'ile the bodyof the block -is cast off-malleable iron or any other suitable material. This method of securing thecleviskrcfcrs-to double blocks only. v

-Wi-th single blocks, such as shown at A,

and in order to relieve said pin from a portion of thestra-iu the checks of the block are which lie parallel withthe shanks of the clevis and prevent it 'from swayiug'to'aud fro, and which come closeup to the bossesjz on the ends of the shanks, as shown particularly in Fig. 2 of the drawings. This block has a-seat, for the beckct Din its end, formed iii-castings, as shown atf, so that the beckct comes" as close to the center of the sheave as possible, and the largest possible h0isting-room is obtained.

By this arrangement cast-iron blocks can be made of any desired ,capacityand much lighter than wooden blocks of equal strength,

and a hoisting-tackle is obtaincd'fwhich is cheap ,.easil y handled, and very durable.

I claim as new and desire to secure by Letters Patent- 1. The clevis B, constructed substantially as described, and combined with the castmetal block A and axispin d,,as explained.

2. Forming the becket-seat into the end of I the block, as and for the purpose specified.

3. The ribs 9 on the checks ofthe blockAj, in combination with the bosses h on the ends of the shanks of the eye, constructed and operatingsubstantially as and for the purpose set forth.

The above specification of v my invent-ion signed by me this 22d day of August, 1865. J." W. NQRCROSS.

Witnesses:

M. M. LmtNcsToN,

G. L. TOPIJIFF. 

